15917-77-8Relevant academic research and scientific papers
Direct NO Reduction by a Biomimetic Iron(II) Pyrazolate MOF
Cai, Zhongzheng,Tao, Wenjie,Moore, Curtis E.,Zhang, Shiyu,Wade, Casey R.
, p. 21221 - 21225 (2021)
A novel metal-organic framework (MOF) containing one-dimensional, Fe2+ chains bridged by dipyrazolate linkers and N,N-dimethylformamide (DMF) ligands has been synthesized. The unusual chain-type metal nodes feature accessible coordination sites on adjacent metal centers, resulting in motifs that are reminiscent of the active sites in non-heme diiron enzymes. The MOF facilitates direct reduction of nitric oxide (NO), producing nearly quantitative yields of nitrous oxide (N2O) and emulating the reactivity of flavodiiron nitric oxide reductases (FNORs). The ferrous form of the MOF can be regenerated via a synthetic cycle involving reduction with cobaltocene (CoCp2) followed by reaction with trimethylsilyl triflate (TMSOTf).
Selectivity-directing factors of ammonia oxidation over PGM gauzes in the Temporal Analysis of Products reactor: Secondary interactions of NH3 and NO
Perez-Ramirez,Kondratenko,Kondratenko,Baerns
, p. 303 - 313 (2008/10/09)
Factors that direct the selectivity of ammonia oxidation for NO were determined previously (J. Catal. 227 (2004) 90) by the investigation of primary NH3-O2 interactions over pure Pt and Pt-Rh (95-5) alloy gauzes at 973-1173 K in the temporal analysis of products (TAP) reactor. A solid mechanistic understanding of the processes leading to by-products (N 2O and N2) requires an analysis of secondary NH 3-NO interactions, which we investigated in the TAP reactor with isotopically labeled molecules. Our experiments under transient vacuum conditions indicate that these secondary processes determine the reaction selectivity for N2O and N2 in high-temperature ammonia oxidation over noble metal catalysts. Adsorbed oxygen species initiate the reaction of ammonia with nitric oxide. N2O originates from the coupling of ammonia intermediates (NHx) and nitric oxide. Different reaction pathways leading to N2 have been identified, including primary (NH3 oxidation) and secondary (NHx and H-assisted NO reduction) processes. The relative contributions of these routes depend on the surface coverage of nitrogen and hydrogen-containing species. A reaction scheme accounting for our experimental observations has been proposed, giving rise to an improved mechanistic description of the complex processes in ammonia burners.
Structure, Harmonic Force Field and Hyperfine Coupling Constants of Nitrosyl Chloride
Gotehouse, Bethany,Meuller, Holger S. P.,Heineking, Nils,Gerry, Michael C. L.
, p. 3347 - 3356 (2007/10/03)
The pure rotational spectra of five isotropic species of nitrosyl chloride were measured using a cavity pulsed microwave Fourier-transform spectometer.Some a-type transitions of all five isotopomers, and some weak b-type transitions of four of these isotopomers were measured in the 4-26 GHz frequency range.Precise values for the rotational constants and the quartic centrifugal distortion constants were obtained.The rotational constants were used in structure determinations and the centrifugal distortion constants were used in a refinement of the harmonic general valence force field.A harmonic central valence force field was also calculated.Hyperfine structure in these transitions arising from quadrupole and spin-rotation coupling interactions was also observed.Diagonal and off-diagonal quadrupole coupling constants and diagonal spin-rotation coupling constants of both the chlorine and nitrogen nuclei were determined.The principal quadrupole coupling constants were evaluated and used to calculate the approximate ionic character of the N-Cl bond.The spin-rotational coupling constants were used to calculate the diamagnetic shielding factor for the nitrogen nucleus; the magnitude of this value indicates a fairly ionic N-Cl bond.
Laser-initiated half-reaction. Vibrational and rotational state distribution of NO produced from the reactant pair O(1D)*N2O
Honma, Kenji,Fujimura, Yo,Kajimoto, Okitsugu,Inoue, Gen
, p. 4739 - 4747 (2007/10/02)
The vibrational and rotational state distribution was measured for NO produced from the reaction O(1D) + N2O -> 2NO via a reactant pair O(1D)*N2O, which, in turn, formed by the 193 nm photolysis of the N2O dimer.The dimer was generated by the supersonic expansion through a pulsed nozzle.The distribution was determined by using the laser-induced Huorescence of NO on its A-X transition.The rotational distribution was of the Boltzmann type characterized by a low temperature, 60-100 K, at each vibrational level measured.The vibrational distribution was found to be composed of the two components, one very cold and the other relatively hot.The experiment using an isotopically labeled N2O revealed that the vibrational energy was not equally distributed over two kinds of NO; the NO originally present in N2O was vibrationally cool while that formed from O(1D) and the terminal nitrogen of Nz0 was vibrationally hot.These results indicate that the reaction occurring is the abstraction of the terminal nitrogen by O(1D).The low rotational temperature, which sharply contrasts with the extremely high rotational excitation observed for the ordinary bimolecular reaction, can be rationalized by considering the geometrical difference in the encounter between the O(1D) atom and N2O.This fact, in turn, indicates that the product energy distribution is significantly atfected by the orientation in the reactive encounter.
